Reversible feeding mechanism for sewing machines



P 17, 1940- G. A. FLECKENSTE'IN ,668

REVERSIBLE FEEDING MECHANISM FOR SEWING MACHINES Filed Sept. 12, 1959 amnion Georye v2 ZZwkenatein WM a Patented Sept. 17, 1940 UNlTED STATES REVERSIBLE FEEDING MECHANISM FOR SEWING MACHINES George A. Fleckenstein, Stratford, Conn., assignor to The Singer Manufacturing Company, Elizabeth, N. J., a corporation of New Jersey Application September 12, 1939, Serial No. 294,445

4 Claims.

This invention relates to sewing machines and more particularly to the work-feeding mechanism of such machines.

The invention has for an object to provide a sewing machine work-feeding mechanism with simple and efficient means for governing the am plitude and direction of work-feeding movements of the work-feeding element. Another object of the invention is to provide a reversible workfeeding mechanism which is well adapted for incorporation below the cloth-plate or bed-plate of a box-type or flat bed family sewing machine.

With the above and other objects in View, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawing of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

Of the accompanying drawing, Fig. 1 is a perspective view of a sewing machine feeding mechanism embodying the invention, the feed-regulator being set for maximum stitch-length, feeding forward. Fig. 2 is a similar view with the feed-regulator set for maximum stitch-length, feeding backward.

In the preferred embodiment of the invention .;rated there is the usual sewing machine -plate 5 which is slotted at 2 to admit the dog 3 which rises and falls in the slot 2 and s given feed-and-return movements lengthwise f such slot. The feed-dog 3 is carried by the the feed-rocker arm 6 fast on the feed rock-shaft l suitably journaled below the bed of the frame of the machine. The feed-bar 4 is slotted at 8, as usual, to embrace the feed-lift cam or eccentric 9 fixed by the set-screw ill to the main-shaft ll also suitably journaled below the bed of the sewing machine frame. The feed rock-shaft 1 carries a crank-arm [2 which is formed with a slideway l3.

Offset from but parallel to the feed rock-shaft l is the feed-regulating shaft I4 to one end of which is fixed the cylinder I5 formed in its free end with a guideway 16 which is in face-to-face relation with the slideway l3; the axis of the shaft [4 being preferably disposed between the axes of the shafts l and I I.

Fixed to the main-shaft is the feed-eccentric 21 into cylindrical bearing engagement with which is one end of the pitman l8 carrying at its opposite end a cross-pin l9 which projects at its opposite ends into the guideway 16 and slideway l3, respectively.

The rock-shaft I4 carries a crank-arm l9 which is connected by the link 20 to the feed-regulator lever 2| fulcrumed at 22 in the bracket-arm standard of the machine-frame and having at its opposite end a thumb-nut 23 by which the lever 2| may be manipulated and tightened in adjusted position to the slotted scale-plate 24.

It will be observed that the guideway 16, which controls the side-throw movements of the crosspinned end of the pitman I8, is adjustable into and across a position of parallelism with the slideway to provide a zero or reversal of feeding movement of the feed-dog.

The spring 25 takes up any lost motion between the cam or eccentric 9 and the slot 8. It also takes up any lost motion between the cross-pin l9 and the slideway l3 and guideway I6.

The pitman I8 is a simple plate-like part and is held between the cheek-pieces or flanges 26 of the eccentric I! so that it cannot tilt laterally relative to or cramp said eccentric.

Having thus set forth the nature of the invention what I claim herein isn- 1. In a sewing machine, a rotary crank, a pitman actuated thereby, a manually adjustable guideway with which said pitman has a sliding connection for controlling and regulating the amplitude of side-throw movements of said pitman, and a work-feeding element having a slip-joint connection with said pitman, whereby said feeding element is actuated by said side-throw movements, said sliding connection being adjustable into and across a position of parallelism with said slip-joint connection, whereby zero and reversely timed work-feeding movements of said feeding element may be obtained.

2. In a sewing machine, a rotary crank, a pitman having at one end a cylindrical bearing engagement with said crank, a cross-pin at the other end of said pitman, a manually adjustable guideway engaged by one end of said cross-pin, and a driven crank-arm having a slideway engaged by the other end of said cross-pin.

3. In a sewing machine, a rotary crank, a pitman having at one end a cylindrical bearing engagement with said crank, a cross-pin at the other end of said pitman, a manually adjustable guideway engaged by one end of said cross-pin, and a driven crank-arm having a slideway engaged by the other end of said cross-pin, said guideway being adjustable into and across a position of parallelism with said slideway.

4. In a sewing machine feeding mechanism, a feed-rocker including a slotted crank-arm member, a feed-governor including a slotted governor member in face-to-face relation with said slotted crank-arm member, and an actuating member having projections received in said slotted members and slidable therein.

GEORGE A. FLECKENS'IEIN. 

